Traffic counting apparatus



Sept. 24, 1963 P. D. scHwAni 3,

TRAFFIC COUNTING APPARATUS Filed June 1. 1959 s Shets-Sheet 1 E69 ECIO ECII ECIZ D9 ODlO ODll OD|2 C? U U C3 IDI ID2 IDS 104 we no? me 105 ENTRANCE v v EX'T RELAY cmcun'mi RELAY CIRCUIT i l, I}: =il

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TRAFFIC couu'rmc APPARATUS Filed June 1, 1959 s Sheets-Sheet a m 0 u MMT J mm A I A wow 98 :8 8 7 v/l| U U a INVENTOR. PETER D. SCHWARZ Ha on)? i Tum United States Patent 3,105,221 TRAFFIC COUNTING APPARATUS Peter D. Schwarz, 61 Woodcrest Drive, Rochester 10, NY. Filed June 1, 1959, Ser. No. 817,235 21 Claims. (Cl. 340-51) The present invention relates to trafiic counting apparatus, and more particularly to an improved system of trafiic counting for determining the number of spaces available in a parking area.

At the present time, parking garages which have many levels for parking are in operation. These modern park ing garages may have separate entrances or have a multilane roadway leading into the garage which serves as both an entrance and an exit. In order to attract vehicles and make it easy for the automobiles to enter such a garage there must be wide entrances and exits, and wide ramps with a large turning radius leading to the various levels. Also in order to provide for uniform and eflicient flow of traffic entering and leaving the garage, and to prevent vehicles from entering the garage when there is no parking space available therein, it is desirable that such a garage have apparatus for informing the driver prior to entering the area if there is a parking space available in the structure, and for then directing him to the nearest area or level where parking space is available. It is evident that vehicles entering and leaving such garages present problems for such a trafiic counting system. For example, a vehicle may occupy more than one lane when entering the parking garage, a plurality of vehicles may enter the garage abreast or simultaneously, small vehicles may enter the garage occupying a small portion of only one lane or straddling both lanes, vehicles may enter and stop, stop and then roll back while waiting fora car in front of them, and then go forward again, or vehicles already in the garage may actuate the detection apparatus in a reverse direction in turning or attempting to occupy a parking space.

Such non-uniformity of traffic patterns, stopping, backing up, and the like creates problems which do not exist in the counting of trafiic on highways or streets for sig nal control or survey purposes. If a small percentage of error exists in counting apparatus used on highways or streets caused by an occasional non-uniform traflic movement, it does not affect the overall efiiciency of the system. However, a one or two percent error in traffic count in a parking garage or lot can result in an error of from fifty to one hundred percent of the indicated total available parking spaces over a given short period of time. For example, in an eight level ramp which holds sixty-five vehicles on each level and has an approximate turnover of six vehicles per space during a twenty-four hour period, the total number of cars which occupy such a garageduring such a period is approximately three thousand. Thus, it the detector is in error even two percent, for example, the count-er will be in error approximately sixty vehicles during the twenty-four hours, which is almost the total capacity of one level in the garage.

One of the objects of the present invention is to provide an apparatus for detecting and counting vehicles entering and leaving a parking garage so that the available parking spaces will be accurately registered at all times.

Another object of this invention is to provide a system of the character described that will accurately register a single vehicle entering or leaving through either lane of a multislane roadway.

Another object of this invention is to provide a system of the character described which will accurately register a single vehicle straddling more than one lane of a multi-lane roadway.

3,105,2Zl Patented Sept. 24, 1963 Another object of this invention is to provide an improved system of the character described which will accurately register several vehicles traveling abreast or in an overalapping fashion when entering or leaving a parking garage.

A further object of this invention is to provide a system of the character described which will accurately register a plurality of vehicles simultaneously entering and leaving a parking area.

A further object of this invention is to provide a system of the character described wherein the accuracy of the system is not affected by vehicles occupying the detection portion of the apparatus and then going in a reverse direction prior to entering the parking garage.

A still further object of this invention is to provide a vehicular detecting system for a parking garage wherein the accuracy of the system will not be ailected by a car backing into the detection area from an adjacent parking space in the garage before leaving the garage.

A further object of this invention is to provide a system of the character described which will accurately register cars of all known sizes presently manufactured and regardless of the traific pattern they assume when entering the parking area.

A still further object of this invention is to provide a system of the character described which will add or subtract the number of available spaces in the parking area in accordance with the direction in which a vehicle travels relative to the detecting portion of the apparatus.

A still further object of this invention is to provide an apparatus for registering trafiic and indicating the spaces available in a parking area, which may be installed in any parking area or garage regardless of the entrance and exit facilities available.

A still further object of this invention is to provide a system of the character described for registering available spaces in a parking area which is dependable and simple in its operation and may be easily installed in any existing parking installation.

Other objects of this invention will become apparent from the drawings, the specification, and the appended claims.

In the drawings:

FIG. 1 is a diagrammatic view of a typical parking area, in which a system made according to one embodiment of this invention is employed, showing the position of the entrance and exit detectors in the roadways of the area and also showing in block form the circuitry for operating a counter operatively connected in the circuit;

FIG. 2A is a diagrammatic view showing in detail the circuitry for registering vehicles passing over the detection apparatus in either direction in the entrance roadway to the parking area;

FIG. 2B is a diagrammatic view showing in detail the circuitry for registering vehicles passing over the detection apparatus when leaving the parking area;

FIG. 3 is a plan view of a coil such as may be in the system of the invention and installed in a section of roadway and adapted to be used for detecting the presence of a vehicle, and showing a typical detection circuit in simplified form;

FIG. 4 is a sectional view showing the detecting coil mounted in the roadway; and

FIG. 5 is a diagrammatic view showing a modified circuit for preventing under certain circumstances the system from inaccurately registering when a vehicle backs into the entrance from an adjacent parking area;

Referring to FIG. 1, this embodiment of the invention is shown as being installed in the entrance and exit level of a parking garage generally denoted at lll. In the instance illustrated, this-level has a dual lane entrance roadway and a separate dual lane exit roadway. Within the garage are a plurality of parking spaces denoted as 12. Located in the entrance roadway of the parking garage are a plurality of detecting coils referred to as C1 through C8 and in the exit roadway of the garage are a plurality of detecting coils referred to as EC9 through EC12. In

the system of the present invention passage of a vehicle over the coils C or EC operates, respectively, the en'- tranc'e circuitry or the exit circuitry which will .be described indetail later, to indicate on a suitable'indicator,

such as 14, located in the oifice of the garage, the subtraction from or addition to the number of spaces avail- The coils C5 through C8 are aligned behindand adja-' cent to the respective coils C1 through C4 and constitute the second row of coils that areinfluenced by a vehicle entering the parking area after the vehicle has influenced an adjacent coil or coils in the first row. Similarly, the

coils EC9' through EC12 are spaced across the exit road- I way of the parking area so that a vehicle leaving the parking area will affect at least one, and not more than two, of adjacent coils E09 through ECIZ.

The coils C1 through 08 and EC9' through ECIZ may be installed in the roadway. as shown in FIGS. 3 and 4.

Each of the coils C1 through C8 and EC9 through ECIZ is positioned in a rectangular channel (FIGS. 3 and 4) that is embedded in the roadway; and the coil is then covered with an epoxy resin 24 to protect it from the I wheels of passing vehicles.

4 operate also through conventional pawls to advance stepby-step ratchet wheels, but these ratchet wheels 50 and 52, respectively, are advanced in a direction opposite to that of the ratchet wheels and 32. The ratchet wheels 30 and 50 are differentially connected by a bevel gear dilferential 38 comprising the pinions 34 and side gears 35 and 37. The ratchet wheels 32 and 52 are differentially connected by a bevel gear dilferential 48 comprising the pinions 44 and side gears 45 and 47. The ditierential 38 is connected to operate a gear 54 which is in mesh with a gear 56. The dilierential 48 is similarly connected to a gear 58; which is inrnesh with gear 60. The gears 56 and 603 are rigidly connected to the side gears 65 and 63, respectively, of a bevel gear differential68 which comprises these side gears and pinions 62. Differential 68 operates the indicating mechanism 14. Thus the energizing of the solenoid 18- moves the ratchet wheel 39 in one direction to drive the counter 14 in a direction to denote one less available parking space in the garage.

The simultaneous energizing of solenoids 1S and ZS opcrates the ratchet wheels 30 and 5G to move the indicator two steps in this same direction to indicate two less available parking spaces in the garage. The solenoid 1A8 operates the ratchet wheel 5% in the other direction to operate the counter to indicate an additional parking space; and simultaneous energizing of relays. 1A8 and ZAS causes the indicator 14 to. move sufliciently toin- 'dicate two more available parking spaces in the garage.

The simultaneous energizing of relays 1S and 1A8 or the simultaneous energizing of relays 2S and 2A3 through the differential gearing, causes the gears $4 and 58, re-

' spectively, to remain stationary, thus no change is indi- 'cated inthe number of available parking spaces.

Associated with each coil C1 through 08 is a detector ID1 through ID8 (FIG. 1), respectively, and associ-' a circuit to a respective detector ID or OD which ina cludes the coil, a battery 16 or other source of energy, and the winding of a relay DR. When a vehicle passes over a coil C or EC, it magnetically unbalances the current in the detector circuit for deenergizing a relay wind ing such as DR. Thus each coil C and EC may have a permanent magnet core so that as-the vehicle goes over the coil, the air gap is replaced by the metal of the vehicle thus increasing the flux-density of the coil which increases the resistance in the coil. The increased resistance causes decrease in current in the relay winding DR thus causing the contact 17 of the relay to drop away. The dropping away of the contact 17 closes a circuit for energizing a relay, such as IR, which is included in the entrance and exit relay circuitry as will be described in detail hereinafter,

ing the counter to add to the number of parking spaces 7 indicated to be available.

The solenoids 1S and 28, when energized, operate; through conventional pawls, ratchet wheels 3% and 32, respectively, to advance each ratchet wheel one step "at a time in one direction. The solenoids 1AS' andZAS 1 In FIGS. 2A, 2B and 5, the relays of the entrance and exit circuitry are shown in their normal positions as when no vehicles are influencing any of the coils C or EC to activate their associated detectors 'ID or OD respectively. When a relay winding is deenergized, all of its associated contacts are in their dropped away posi tion, and when the winding of a relay is energized, its associated contacts assume a picked up position to close a front contact. In some instances, back contacts are provided to be closed when a respective relay winding is deenergized. The symbols denote a suitable connection to the positive terminal or a battery or other source of energy, and the symbols denote a connection to a negative terminal or ground connection of a suitable source of energy.

The entrance and exit circuitry will now be'described. Referring to FIGS. 2A and 2B, each of the detector units ID1 through IDS is connected to an associated relay IR. There are eight of these relays 1R1 through 1R8. Each such relay is energized in response to the activation of Each such relay is energized in response to the activation of its associated detector. The energizing of each relay 1R1, 1R2, IR3, 1R4, IRS, 1R6, 1R7, IRS, 0R9, ORR}, OR11, and OR12 causes a pair of contacts, and 13%, 101 and 114, 112 and i132, 128 and 115, 1% and 134, and 135, and 136-, 126 and 127, 142 and/162, and 167,163 and 168,'and164 and 16 9', respectively, which are associated with the respective relays to pick up.

Relay 1FX is provided to be energized in response to the picking up of any one of the relays 1R1 through 1R4 which occurs when a single vehicle occupies the entrance roadway to the parking garage in either one of the "entrance lanes or straddling ot the lanes. Relay ZFX is provided to be energized by the. picking up of any two non-adjacent relays such as 1R1 and IRS, IRZand IR4, or 1R1 and 1R4. This condition exists when more than one vehicle is in the entrance section of roadway influencing two or more coils C1 through C4 of'which at least two of the influenced coils are non-adjacent. The energizing of the winding of relay lFX causes its contact which extends from and picked up,

102 to shift from back to front. The energizing of relay 'ZFX causes its contact 116 to shift from back to front.

Relay 1RX is provided to be energized by the picking up of any one of the relays 1R5 through 1R3 which occurs when a single vehicle passes over any one of the second row of coils C5 through C8. Relay 2RX is energized by the picking up of any two non-adjacent relays of group IRS through 1R3, such as relays 1R5 and 1R7, 1R6 and 1R8, or IRS and IRS which would be caused by the presence of two vehicles occupying the roadway in such a way as to influence the second row of coils C5 through C8 in a manner similar to the influence to the first row of coils C1 through C4 by the presence of more than one vehicle in the detecting section of the roadway. The energizing of the winding of relay IRX causes its contact 197 to shift from back to front. The energizing of the winding of relay ZRX causes its contact 122 to shift from back to front.

Transfer relay TR, which is a slow drop-away relay, is energized whenever relay ZFX is picked up. Ordinarily relay 1RX would be energized when the first of two vehicles which occupied the first row of coils C1 through 04 continued on to the second row of coils C5 through C8. However, relay TR causes relay ZRX to be picked up first when a single vehicle passes over any one of the second row of coils C5 through C3 while relay ZFX is picked up. Also relay TR when energized causes the relay 1RY to drop away before relay ZRX when the first of two adjacent or overlapping vehicles clears the second row of coils C5 through C8. The energizing of the winding of relay TR cause-s both its contacts 1% and 13 7 to shift from back to front;

Relays 1FY and ZFY are energized when coils C1 through C4 are influenced by a vehicle, and coils C5 through C8 have not yet been influenced by a vehicle. These FY relays condition the entrance circuitry so that a solenoid 13 or 28 respectively, is energized when a vehicle entering the parking area uncovers the first row of coils C1 through C4. The energizing of the winding of relay 1FY causes its contacts 1198 and 169 to shift from back to front. The energizing of relay ZFY causes its contacts 123 and 124 to shift from back to front.

Relays 1RY and ZRY condition the entrance circuitry so that a solenoid 1A5 tor 2A8, respectively, will be on ergized when a vehicle traveling in a reverse direction in the entrance roadway clears the second row of coils C5 through C3. The energizing of relay 1RY causes its contacts 103 and 149 to shift from back to front; and the energizing of relay ZRY causes its contacts 117 and 119 to shift from back to front.

A more detailed description of the function of the circuitry and the various relays will be given in connection with the description of the operation of the system under typical operating conditions.

Assuming a vehicle enters the parking area to first cover both coils C1 and C2, the associated detectors ID1 and IDZ are activated which causes the energizing of relays 1R1 and 1R2. In response to the picking up of either 1R1 or 1R2, relay llPX is energized by a circuit includes front contact 1% of relay 1R1 or front contact 1111 of relay 1R2, and the winding of relay 1FX to In response to the picking up of relay 1FX, relay IFY is energized by a circuit which extends from and includes front contact 102 of relay IFX, back contact 163 of relay 1RY, and the winding of relay 1FY to The vehicle then. proceeds across coils C5 and C6 before leaving coils C1 and C2, thus picking up relays 1R5 and 1R6. In response to the picking up of relays IRS and 1R6 relay 1RX is energized by a circuit which extends from and includes either front contact 1G4 of relay 1R5 or front contact 195 of I relay 1R6, back contact 1% of relay TR, and the winding of relay 1RX to The picking up of relay llRX provides :a stick or hold-in circuit for holding relay 1FY which circuit extends from and includes the relay ZRX front contact 107 of relay 1RX, front contact 108 of relay 1F! and the winding of relay 1FY to When the vehicle leaves the coils C1 and C2 relays 1R1 and 1R2 are deenergized to open the pick up circuit for relay 1FX. The dropping away of relay 1FX closes its back contact 1&2 which completes a circuit for energizing solenoid 13, which circuit extends from and includes back contact 162 of relay llFX, front contact 109 of relay dFY, and the winding of solenoid 18 to The energizing of the solenoid 18 operates the ratchet wheel 39 to move the counter 14 back one digit thus indicating that there is one less available space in the parking area. As the car proceeds into the parking area it uncovers coils C5 and C6 which results in the dropping away of relays IRS and 1R6 thus deenergizing relay lRX. The dropping away of relay lRX breaks the previously described stick or hold-in circuit for relay IFY at front contact 1 2 7 of relay 1RX thus causing relay 1FY to drop away which deenergizes the solenoid 18 by opening its previously described pick-upcircuit.

For another example, assume that two vehicles enter the parking area abreast, the first vehicle straddling both lanes of the roadway so that it activates the detectors associated with coils C2 and C3 of the first row and the second vehicle entering so that it activates the detector associated with coil C4. In response to the activation of detectors ID2, IDS and D4, relays IR2, IRS and 1R4 are energized. In response to the picking up of R2 or 1R3; whichever is first, relay llFX is energized by a circuit which includes either contact 1G1 of relay 1R2 or contact 112 of relay 1R3. The picking up: of relay 1R4 when two cars are covering the first row of coils causes the picking up of relay ZFX by a circuit which extends from and includes front contact 114 of relay 1R2, front contact 115 of relay 1R4 and the winding of relay ZFX to T he picking up of relay 1 FX energizes the relay IFY through its previously described pick-up circuit. The picking up of relay ZFX energizes relay ZFY by a circuit which extends from and includes front contact 116 of relay ZFX, back contact 117 of relay ZRY and the winding of relay ZFY to Simultaneously with the picking up of relay ZFX relay TR is energized by an obvious circuit which extends from and includes front contact 118 of relay ZFX.

Assuming that the second vehicle stops and covers coil C without proceeding forward while the first vehicle proceeds to cover coils C6 and C7, relays 1R6 and 1R7 are energized in the manner previously described which causes the picking up of relay ZRX by a circuit which extends from and includes either contact 1G5 of relay 1R6 or contact 128 of relay 1R7, front contact 1% of relay TR and the Winding of relay ZRX to It should be noted that the presence of two vehicles over coils in the first row resulted in the picking up of the relay TR which caused the relay ZRX to be energized instead of relay llRX when the first vehicle covered a coil or coils of the second row before it uncovered the coils of the first row. In response to the picking up of relay ZRX a stick or hold-in circuit is provided for relay ZFY which extends from and includes front contact 122 of relay ZRX, front contact 123 of relay ZFY and the winding of relay ZFY to Relay Z-FY is now being held in its picked-up condition by relay ZRX, thus as the first vehicle leaves the first row of coils, relay ZFX is deenergized by the opening of front contact 114 of relay IR2 which causes the pick-up circuit for relay TR to be broken at front contact 118.

The dropping away of relay ZFX closes a circuit for energizing the solenoid 28 which extends from and includes back contact 116 of relay ZFX, front contact 124 of relay ZFY and the winding of solenoid 2S it should be noted that the relay TR has a delayed drop- :away action after its pick-up circuit is broken so that will not become deenergized through the opening of front contact 1% of relay TR before relay 2FX has an opportunity to establish the pick-up circuit for the solenoid 28.

The relay ZRX must be maintained energized so as to maintain the stick or hold-in circuit for the relay ZPY so that its front contact 124 will remain closed. When relay TR drops away, relay 2RX is deenergized by opening its previously described pick-up circuit thus causing the dropping away of relay ZFY which causes the deenergizing of the solenoid 23. The closing of back contact 106 of relay TR causes relay lRX to pick up by a circuit which extends from and includes either front contact 105 of relay 1R6 or front contact 120 of relay 1R7 in the previously described pick-up circuit for the relay ZRX.

Assuming that the first vehicle passes beyond the second row of coils before the second vehicle occuipes a coil in the second row, relays 1R6 and relays 1R7 are deenergized which causes relay lRX to drop away. As the second vehicle moves forward, it covers coil C8 of second row of coils thus picking up relay 1R8 which energizes relay 1RX by a circuit which extends from and includes front contact 126 of relay 1R8, back contact 1% of relay TR and the winding of relay lRX to The picking up of relay IRX causes the previously described stick or hold-in circuit for relay lFY to be reestablished. As the second vehicle leaves coil C4 relay lFX is deenergized. The dropping away of relay lFX energizes the solenoid 18 through its previously described pick up circuit. As the second vehicle leaves'coil C8 relay IRS is deenergized which causes the dropping away of relay lRX which breaks the previously described stick or hold-in circuit for lFY thus deenergizing the solenoid Now assume that a vehicle enters the parking area to first cover coil C1, relay I-Rl is deenergized which picks up relay rlFX through the front contact 1% of relay 1R1. This causes the energizing of relay llFY as previously described. The further proceeding of this vehicle over coil C5 results in the picking up of relay lRX that provides the stick or hold-in circuit [for relay lFY. Now assuming that another vehicle enters the parking area to first cover coils C3 and C4 relays, 1R3 and 1R4 are picked up which causes the picking up of relay ZFX by a circuit which extends from and includes front contact 130 of relay 1R1, front contact 132 of relay IRS and winding of relay 2FX to The picking up of relay 2FX causes the picking up of relay TR as previously described which results in the deenergizing of relay lRX by the opening of back contact 1% of relay TR. The closing of front contact 1% causes relay ZRX to pick up. Since the first vehicle is still influencing coil C4 relay lFY is not aifected by this dropping away of relay 1RX. The picking up of relay ZRX establishes the previously described stick or hold-in circuit for relay ZFY. The second vehicle then covers coils C7 and C8 which causes the picking up of relays IR7 and IRS thus energizing relay 1RX by a circuit which extends from and includes front contact 134- of relay 1R5, front contact 136 of relay 1R7, front contact 137 of relay TR and the winding of relay '1RX to The picking up of relay llRX reestablishes the stick or hold-in circuit for relay lFY. At this point both vehicles are covering coils in both rows simultaneously.

Assuming that one vehicle first uncovers coil C1 in the first row, relay 1R1 is dropped away which breaks the pick-up circuit for 2FX. The dropping away of relay ZFX opens the pickup circuit for relay TR and closes the pick-up circuit for solenoid 28 as previously described which causes the indicator 14 to subtract an available space from the total it shows. When the contacts 1% and 137 of the relay TR shift from front to back relays 1RX and ZRX are momentarily dropped away. Since both vehicles are still occupying the second row of coils however, these relays'ilRX and ZRX are picked up again.

Since only one vehicle is occupying the first row of coils,

the dropping away of relay ZRX causes relay ZFY to become deenergized by breaking its previously described stick or hold-in circuit which opens its front contact 124 thus deenergizing the solenoid 28. The presence of the other vehicle over the first row of coils maintains relay 1FY energized even though the relay llRX momentarily is dropped away. 1

Now assuming that the other vehicle leaves the first row of coils, relay lFX is deenergized which energizes the solenoid 13 to cause the indicator to subtract another available space from the total shown. Since relay ZRX was reenergized after its momentary dropping away the closing of its front contact 122 picks up relay ZRY which has no effect on the circuit under these conditions. When the one vehicle leaves the second row of coils relay ZRX is deenergized thus causing relay ZRY to drop away. As the other vehicle leaves coil row 2. relay 1RX is dropped away which causes the dropping away of relay llFY thus deenergizing the solenoid 18.

Assuming that a vehicle backs out of a parking space 12 to cover coil C5, relaylRS is picked up which energizes relay lRX through its previously described pick-up circuit. The picking up of relay lRX closes the pick-up circuit for energizing reiay lRY which extends from and includes front contact 107 of relay 1RX, back contact 108 of relay lFY and the winding of relay 1RY to If this vehicle continues to back up, it then covers coil C1 of coil row 1, which causes the picking up of relay IRfl, thus energizing relay ll-FX. The picking up of relay lFX provides a stick or hold-in circuit for relay lRY, which extends from and includes front contact 102 of relay llFX, front contact 103 of relay 1RY and the winding of relay lRY to At this point if the vehicle reverses its direction and goes forward into the garage to leave by way of the normal exit roadway, coil C1 is uncovered which causes relay 1R1 to drop away thus deenergizing relay lFX. Since the vehicle is still occupying coil row 2 the relay 1RY is held in its picked up position. Since the vehicle next uncovers coil row 2, relay IRS is dropped away which deenergizes relay 1RX.

The dropping away of relay 1RX breaks the pick-up circuit for relay lRY thus restoring the system to normal. In the preceding example neither the solenoid 15 nor the solenoid 1A8 was energized.

In the event that the vehicle merely covered coil row 2 and then proceeded in a forward direction, the relay lRX would cause the picking up of relay lRY, and as the vehicle then proceeded forward the relay lRX and lRY would drop away without adversely affecting the circuit to erroneously actuate the indicator 14. 7

However, if, instead of reversing and then going forward as described above, the vehicle should continue to go in a reverse direction it will pass over and uncover coil row 2 thus deenergizing relay 1R5 which causes the drop ping away of relay lRX. This closes a circuit for energizing the solenoid ilAS which actuates the indicator 14 to denote an additional available space in the parking area. The circuit for energizing solenoid 1A8 extends from and includes back contact 107 of relay llRX, front contact of relay lRY and the winding of solenoid 1A5 to As this vehicle clears coil row 1, relay llFX is deenergized which causes the dropping away of relay 1RY.

It is apparent thatif two vehicles should simultaneously travel in a reverse direction over the coils that a circuit would be established to energize the solenoids 1A8 and ZAS as described previously for the traveling of two vehicles abreast in a forward direction.

Assuming that a vehicle leaves the parking garage in an ordinary fashion and as it is driven out forwardly through the exit covers one of coils E09 through EClZ, say, for instance, coil ECil, the detector unit ODS associated with this coil is activated which energizes the relay 0R9 thus energizing the solenoid ZAS by a circuit which extends from and includes front contact 142 (FIG.

9 2B) of relay R9, wire 166 (FIGS. 2B and 2A) and the winding of solenoid ZAS to After this vehicle clears the row of coils at the exit, relay 0R9 drops away thus deenergizing the solenoid lAS. It is apparent at the exit end of the garage that one or more vehicles may leave simultaneously or in overlapping fashion to energize both solenoids 1A3 and 2A8 as described for the simultaneous energizing of the solenoids 18 and 28 thus causing the indicator 14 to denote two additional parking spaces in the garage. For example, if a second vehicle should cover coil EClZ while coil ECfi'is covered solenoid :ZAS is energized by a circuit which extends from and includes from contact 162 of relay 0R9, back contact 163 of relay ORll, front contact 164 of relay OR12, wire 143 (FIGS. 2A and 2B), and the winding of solenoid lAS to Referring to MS. 5, the entrance circuitry may be modified to include a slow drop-away relay B having a front contact 1nd in the pick-up circuit for the relay lRY. This may be included in an installation if it is desirable to have additional back-up protection in the embodiment shown in FIGS. 2A and 2B as, for instance, where the first and second row of coils may be so spaced or located that cars from adjacent parking spaces may back into the second row of coils, then back into the first row of coils and then while still parking uncover the second row before proceeding forward to the exit. In this event, the vehicle, when hacking into the second row of coils, would cause relay lRX to pick up, which would energize relay B by an obvious circuit which includes front contact 161 of relay llRX. The picking up of relay G3 closes the front contact 160 in the pick-up circuit for relay lRY. This circuit extends from and includes the front contact 107 of relay ilRX, the back contact lliifi of relay lFY, the front contact 160 of relay B and the winding of relay lRY to As the vehicle backs into the first row of coils relay lFX is picked up which provides a stick or hold-in circuit for relay lRY which extends from and includes the front contact 102 of relay l-FX, front contact 103 of relay llRY, and the front contact 160 of relay B and the winding of relay lRY to When the vehicle uncovers the second coil row, relay IRX drops away, thus energizing the solenoid 1A8 to denote an additional available parking space in the garage by a circuit which extends from and includes the front contact 107 of relay l-RX, the front contact 140 of relay .lRY and the winding of solenoid lAS to The dropping away of relay llRX also opens the pickup circuit for the relay B which causes its contact 160 to open thus breaking the stick circuit for relay ZRY permitting it to drop away. Since relay IFX is in its picked up condition, relay lFY is energized when relay IRY drops away by a circuit which extends from and includes the front contact 162 of relay lFX, back contact 103 of relay iRY and the winding of relay lFY to Now when the vehicle proceeds in a forward direction to again cover the second coil row, relay 1RX is again picked up which provides a stick or hold-in circuit for relay llFY through its front contact 107. As the vehicle proceeds forward and uncovers coil row 1, relay lFX drops away which energizes the solenoid 18 by a circuit which extends from and includes the back contact 102 of relay lFX, front contact 109 of relay lFY and the winding of the solenoid 18 to This causes the indicator 14 to subtract an additional available space from the total shown. It is evident that as the car proceeds forward relay IRX drops away which breaks the stick or hold-in circuit for relay lFY thus deenergizing the solenoid 18.

It is obvious that the embodiments of the invention herein disclosed may be expanded so as to be installed in a parking area where the entrance or exit roadway is of sufficient width to accommodate three or more vehicles. It is also contemplated that instead of using coils in the floor as detectors, other means of detection may be used in connection with this invention such as vertical beams of visible light using photoelectric cells, infra red, ultrasonic, or other types of presence detectors, either overhead or embedded in the roadway; or the coils themselves may be located above the vehicles instead of in the floor as long as they operate the circuitry in the manner previously described.

While the invention has been described in connection with a specific embodiment thereof, it will be understood that it is capable of further modification, and this application is intended to cove-r any variations, uses, or adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice in the art to which the invention pertains and as may be applied to the essential features hereinbefore set forth, and as fall which the scope of the invention'or the limits of the appended claims.

Having thus described my invention, what I claim is:

1. A system for counting the number of vehicles passing over a section of roadway of a parking garage or the like, comprising first and second vehicle detectors, one of said detectors being ahead of the other in the direction of movement of trafiic so that said detectors are activated successively by a single vehicle during passage of the vehicle over said section of roadway, a counter for indicating the number of vehicles in said parking garage or the like, means responsive to the activation of said first detector followed by the activation of said second detector and the subsequent inactivation of said first detector for causing said counter to indicate a single Wehicle change in the total number of vehicles in said parking garage, and means responsive to the activation of said first detector followed by the activation of said second detector and the subsequent inactivation of said second detector and reactivation of said first detector, as caused by a vehicle reversing its direction of travel after activating both said first and second detectors, for preventing said counter from indicating a change in the total number of vehicles in said garage.

2. A system for counting the number of vehicles traveling in either direction over a section of roadway leading into a parking garage, comprising a counter for indicating the number of vehicles in said garage, a first electromagnetic means operative when energized to operate said counter to indicate one additional vehicle in said garage, a second electromagnetic means operative when energized to operate said counter to indicate one less vehicle in said garage, a first detector for indicating the presence of a vehicle in said roadway, a second detector for indicating the presence of a vehicle in said roadway, said first and second detector being disposed in the direction of travel relative to one another so that both of said detectors are successively activated by said vehicle but in opposite order, respectively, during travel of the vehicles in opposite directions, respectively, a forward control relay for partially controlling the operation of said first electromagnetic means, a reverse control relay for partially controlling the operation of said second electro magnetic means, a first circuit means responsive to the activation of said first detector when said second detector is in an inactive condition for energizing said forward control relay, a second circuit means responsive to the activation of said second detector when said first detector is in an inactive condition for energizing said reverse conltrol relay, a third circuit means including a front contact of said forward control relay for holding said forward control relay picked up while a vehicle is activating said second detection means regardless of activation of said first detection means, a fourth circuit means responsive to the deactivation of said first detection means and the picked-up condition of said forward control relay for energizing said first electromagnetic means to indicate addition of a single vehicle to the number in said garage,

l l a fifth circuit means including a front contact of said reverse control relay and the activated condition of said first detection means for holding said reverse control relay in a picked-up condition regardless of activation of said second detection means, and a sixth circuit means responsive to the deactivated condition of said second detector and the picked upt'condition of said reverse control relay for energizing said second electromagnetic means to indicate subtraction of a single vehicle from the number in said garage.

3. A system according to claim 9 comprising a seventh circuit means responsive to the deactivation of said second detector for deenergizing said first electromagnetic means and an eighth circuit means responsive to the deactivation of said first detector for deenergizing said second electromagnetic means.

4. A systemfor counting vehicles traveling over a section of roadway leading into a parking area, comprising a counter for indicating the number of vehicles in said parking area, an electromagnetic means operative when activated to operate said counter to indicate a single vehicle change in the number of vehicles in said parking area, a first vehicle detector and a second vehicle detector, said first and second detectors being spaced in the direction of travel for activation of both said detectors by a single vehicle during its travel, a single relay for partially controlling the energizing of said electromagnetic means, a first circuit means responsive to the activation of said first detector for energizing said single relay, a second circuit means responsive to the activation of said second detector and including a contact of said single relay in its energized position for holding said single relay in energized position, and a third circuit means connected to said first circuit means to be operated upon deactivation of said first detector when said second detector is activated and including a contact of said single relay in its energized position for energizing said electromagnetic means to operate said indicator.

5. A system for counting the number of vehicles passing over a section of roadway leading into a parking garage or the like, comprising a counter for indicating the number of vehicles in the parking garage, a first plurality of detectors spaced from one another laterally across the roadway a distance less than the width of a vehicle, a second plurality of detectors spaced trom one another laterally across the roadway a distance less than the Width of a vehicle, said first and second plurality of detectors being spaced from each other in the direction of travel a distance less than the length of a vehicle, means operated by a vehicle passing at least one of said first plurality of-detectors and then at least one of said second plurality of detectors and subsequently clearing said first plurality of detectors for operating said counter to indicate a single additional vehicle in said parking garage, means operated by a second vehicle first passing said first plurality of detectors and then said second plurality of detectors and subsequently clearing said first plurality when a first vehicle is activating said first plurality of 'detectors for causing said counter to indicate another additional vehicle in said parking garage, and means operated by a vehicle first passing one of said second plurality of detectors and then said first plurality of detectors and subsequently clearing said second plurality of detectors for operating the counter to indicate a single less vehicle in the garage, and means operated by a vehicle first passing said second plurality of detectors and then said first detector and subsequently clearing said second detector when another vehicle is occupying said second detectors and traveling in the same direction to indicate another less additional vehicle in said garage.

6 A system for counting vehicles traveling over a section of roadway leading into a parking area, compris ing a counter for indicating the number of vehicles in said parking area, an electromagnetic means operable when activated to cause said counter to indicate a change in the number of vehicles in said parking area, a first vehicle detector and a second vehicle detector, said detectors being so disposed relative to one another that a vehicle entering said parking area first activates said first detector and then subsequently activates said second detector which is'followed by the inactivation of said first detector and the subsequent inactivation of said second detector, a first circuit means responsive to the activation of said first detector followed by the activation of said second detector and the subsequent inactivation of said first detector for energizing said electromagnetic means to cause said counter to indicate the presence of an additional vehicle in said parking area, and a second circuit means responsive to the activation of said second detector followed by the activation of said first detector and the subsequent inactivation of said first detector followed by the inactivation of said second detector preventing the activation of said electromagnetic means whereby a vehicle traveling out of said parking area and then back into said parking area will not cause said counter to indicate a change in the number of vehicles in said area.

7. A system for counting vehicles entering and leaving a parking area, said parking area having a first section of roadway for vehicles entering said parking area and a second section of roadway for vehicles leaving said parking area, each of said sections of roadway being of sufficient width to accommodate at least two vehicles abreast, said system comprising a counter for indicating the number of vehicles in said parking area, a first electromagnetic means operative when activated to operate said counter to indicate a single vehicle entering said parking area and a second electromagnetic means operative when activated to operate said counter to in dicate an additional single vehicle entering said parking area, said first and second electromagnetic means operative when activated simultaneously to cause said counter to indicate tWo vehicles entering said parking area, a

.third electromagnetic means and a fourth electromagnetic detectors activated by the presence of vehicles entering said parking area over said first section of roadway, a second plurality of vehicle detectors activated by the presence of vehicles traveling over said second section of roadway leaving said parking area, said first plurality of detectors being so laterally disposed relative to one another that the presence of a single vehicle in the first section of roadway activates at least one of said first plurality of detectors and not more than said one detector and another adjacent detector, and the presence of two laterally-spaced vehicles in said first section of road- Way activates a third of said first plurality of detectors, said second plurality of detectors being so laterally disposed relative to one another that thepresence of a single vehicle in said second sec-tion of roadway activates at least one of said second plurality of detectors and the presence of two laterally-spaced vehicles in said second section of roadway activates a third of said second plurality of detectors, both of said third detectors being non-adjacent to at least one of the first-named activated detectors, a first circuit means responsive to the activation by a first vehicle of one of said first plurality of detectors to energize said first electromagnetic means, a second circuit means responsive to the activated condition of said first plurality of detectors caused by a second vehicle in said first section of roadway and the presence of said first vehicle for energizing said second electromagnetic means, a third circuit means responsive to the activation by a first exi-ting vehicle of said second plurality of detectors to activate said third electromagnetic means, and a fourth circuit means responsive to the activation of said second plurality of detectors caused by the presence of a second exiting vehicle and the presence of said first exiting vehicle in said second section of roadway for energizing said fourth electromagnetic means, whereby said counter can accurately indicate more than one vehicle entering and more than one vehicle leaving said parking area simultaneously.

8. A system for counting the number of vehicles passing over a section of roadway leading into a parking garage or the like, comprising first and second vehicle detectors, said first detector being spaced ahead of said second in the direction of movement of trafiic, a counter for indicating the number of vehicles in said parking garage or the like, a first means responsive to the completing of a first electric circuit for causing said counter to move in one direction to indicate a single additional vehicle in said garage, a second means responsive to the completing of a second electric circuit for causing said counter to move in the other direction to indicate a single less vehicle in said garage, means responsive to the activation of said second detector by the presence of a vehiclefor partially completing said second circuit, means responsive to the activation of said second detector and then the activation of said first detector by the presonce of said vehicle followed by the inactivation of said second detector when said vehicle clears said second detector when traveling in a direction out of the parking gar-age for completing said second electric circuit, and means responsive to the activation of said second detector and then the activation of said first detector while saidsecond detector is in a state of activation, followed by the subsequent inactivation of said first detector when said vehicle reverses its direction of travel from exiting to entering said parking garage for preventing said counter from registering a vehicle change, said first electric circuit being completed by activation of said first detector followed by the simultaneous activation of said second detector, and the subsequent inactivation of said first detector and said second electric circuit being completed by activation of said second detector followed by the simultaneous activation of said first detector, and the subsequent inactivation of said second detector.

9. A system for counting the number of vehicles passing over a section of roadway leading into a parking garage or the like, comprising first and second vehicle detectors, one of said detectors being spaced ahead of the other in the direction of movement of traffic a distance less than the length of a vehicle, a counter for indicating the number of vehicles in said parking garage or the like, a first means responsive to the completing of a first electric circuit for causing said counter to move in one direction to indicate a single additional vehicle in said garage, a second means responsive to the completing of a second electric circuit for causing said counter to move in the other direction to indicate a single less vehicle in said garage, means responsive to the activation of said second detector by the presence of a vehicle for partially completing said second circuit, meansrespons-ive to the activation of said second detector and then the activation ofsaid first detector followed by the inactivation of said second detector when said vehicle clears said second detector when traveling in a direction out of 'the parking garage for completing said second electric circuit, time delay means responsive to activation of the second detector for partially completing said first electric circuit and responsive to said activation of said second detector during the activation of said first detector followed by the subsequent inactivation of said second detector to register no count upon the counter so as to provide a back up protection, subsequent entry of the vehicle into said parking area causing said first electric circuit to be completed by activation of said first detector followed by the simultaneous activation of said second detector and the subsequent inactivation of said first detector.

10. A system for counting the number of vehicles passing over a section of roadway of a parking garage or the like, said section of roadway being of sutficient width to accommodate at least two vehicles abreast, said system comprising a plurality of detectors laterally spaced across the roadway, each adapted to be actuated by registry therewith of a vehicle, said detectors having an effective lateral spacing from one another less than the width of a vehicle, a counter for indicating the number of vehicles in the par-king garage, and means connnecting said detectors to said counter to actuate said counter, said connecting means being operative to cause said counter to count only once when two adjacent detectors are actuated simultaneously.

11. A system for counting vehicles entering and leaving a parking area, said parking area having a first section of roadway for vehicles entering said parking area and a second section of roadway for vehicles leaving said parking area, each of said sections of roadway being of sufiicient width to accommodate at least two vehicles abreast, said system comprising a counter for indicating the number of vehicles in said parking area, a plurality of vehicle entrance detectors, a plurality of vehicle exit detectors, said plurality of vehicle entrance detectors being so disposed laterally relative to one another that the presence of a single entering vehicle in the first section of roadway activates at least one of said entrance detectors and not more than said one detector and an adjacent entrance detector, and the presence of a second entering vehicle in said first section of roadway and laterally spaced from the first-named single vehicle activates a third of said entrance detectors, said plurality of vehicle exit detectors being so disposed relative to one another that the presence of a single exiting vehicle in the second section of roadway activates at least one of said exit detectors and not more than said one detector and an adjacent exit detector, and the presence of a second exiting vehicle in said second section of roadway and laterally spaced from the last-named single exiting vehicle activates a third of said exit detectors, said third detectors being non-adjacent to at least one of the first-named activated detectors of said entrance detectors and said exit detectors, two differentials, each of said dififerentials having three elements, means connecting said entrance detectors to a first element of one difierential to advance said first element in one direction upon registry of a vehicle with one and not more than two adjacent entrance detectors, said connecting means being operative to advance a first element of the second difierential in said one direction upon entry of two vehicles simultaneously, a second means connecting said exit detectors to a second element of one difllerential to advance said second element in the other direction upon registry of a vehicle with one and not more than two adjacent exit detectors, said second connecting means being operative to advance a second element of the second difierential in said other direction upon the leaving of two vehicles simultaneously, a third differential having three elements, means connecting the third elements of the first two differentials, respectively, to two difierent elements respectively of the third differential, and means connecting the third element of the third differential to the counter to actuate said counter upon actuation of any element of the first two diiferentials.

12. A system for counting the number of vehicles passing over a section of roadway of a parking garage or the like, said section of roadway being of suficient width to accommodate at least two vehicles abreast, said system comprising a plurality of detectors, each adapted to be actuated by the registry therewith of a vehicle, said detectors having an efiective lateral spacing from one an- 15 other less than the width of a vehicle, a counter for in dicating the number of vehicles in the parking garage, and means connecting said detectors to said counter to actuate said counter, said connecting means being operative to cause said counter to count only once when two laterally adjacent detectors are actuated simultaneously and being further operative to cause said counter to count twice when two laterally non-adjacent detectors are actuated simultaneously.

13. A system for counting the number of vehicles passing over a section of roadway of a parking garage or the like, said section of roadway being of suflicient width to accommodate two vehicles abreast, comprising a plurality of pairs of vehicle detectors spaced from one another transversely of the direction of vehicle travel, each pair consisting of first and second vehicle detectors spaced from one another in the direction of vehicle travel, so that they are activated successively by a vehicle traveling over said section of roadway, said pairs of :detectors being so laterally disposed relative to one another that the travel of a single vehicle over said section of roadway activates the detectors of one pair and not more than said one pair of detectors and another adjacent pair of detectors, and travel of a second vehicle over said section of roadway in laterally-spaced relation to the first vehicle activates a third pair of detectors, said third pair of detectors being non-adjacent to at least one of said first two pairs, :a counter for indicating the number of vehicles in said garage, means responsive to the activation of thefirst detector of any one of said pairs for partially completing a first electric circuit, means responsive to the activation of the second detector of any one of said pairs followed by inactivation of the first detector of any one of said pairs when either of said =vehicles clears the previously-activated first detector for completing said first circuit, and means responsive to the activation of another of said second detectors followed by the inactivation of another one of said previously-activated first detectors ttor completing another electric circuit, means responsive to the completing of a first of said electrical circuits for causing said counter to indicate a single change in the number of vehicles in said parking garage, and means responsive to the completing of a second of said electrical circuits for causing said counter to indicate a second single change in the number of vehicles in said parking garage.

14. A system for counting the number of Vehicles traveling over a section of roadway leading into a parking garage or the like, said roadway being of sufficient width toaccommodate at least two vehicles abreast, comprising a counter for indicating the number of vehicles, a plurality of vehicle detection means arranged in first and second rows, said rows being perpendicular to the direction of vehicle travel and spaced from one another along the direction of vehicle travel a distance sufiicient for activation of at least one detection means in each row by a single vehicle during a portion of its path of travel, said detection means being so positioned laterally with respect to one another in each row that at least two non-adjacent detection means in each row are activated in response to the presence of two vehicles traveling abreast of one another in said section of roadway, and a detection means of one row being aligned with a detection means of the other row in the direction of vehicle travel, means responsive to the activation of one of said detection means of said firs-t row followed by activation of the aligned detection means of said second row, and the subsequent inactivation of said one detection means of said first row 'for completing a first electric circuit to actuate said counter to indicate a single change in the number of vehicles in said garage or the like, and means responsive to the activation of one of the non-adjacent detection means in said first row caused by the presence of an addditional laterally-spaced vehicle and to the activation of said one of said first row detection means and to the activation of said aligned detection means of said second row, and to activation of the non-adjacent detection means in the second row, which is aligned with the first-named non-adjacent detection means, followed by the inactivation of said non-adjacent detection means of said first row for completing a second electric circuit, to actviate said counter to indicate an additional vehicle change simultaneously with the indication of the vehicle change in response to said first circuit means.

15. A system for counting vehicle traveling over a section of roadway leading into a parking area, said section of roadway being of sufi'icient width to accommodate at least two vehicles abreast, comprising a counter for indicating the number of vehicles in said parking area, first means operative to operate said counter to indicate a single vehicle change in the number of vehicles in said 7 parking area, a second means operative to indicate an additional single vehicle change in the number of vehicles in said parking area, a plurality of vehicle detectors arranged in first and second rows and activated by the presence of vehicles traveling in said roadway, said rows being spaced from one another in direction of vehicle travel, said detectors being so disposed laterally that travel of a single vehicle in said section of roadway activates at least one of said detectors in both rows and not more than one adjacent detector in each row, and the presence of two laterally-spaced vehicles in said roadway activates at least a third of said plurality of detectors in each row, said third detector in each row being non-adjacent to at least one of the detectors activated by the first vehicle, a relay associated with each of said detectors, means connecting each of said relays to its associated detector to energize said relay when said associated detector is activated by the presence of a vehicle, means responsive to the energizing of any one of the relays associated with said first row detectors for partially completing an electric circuit, means including two relays associated with non-adjacent detectors for partially completing a second electric circuit, means responsive to the energizing of any one of the second row relays and responsive to the deactivation of all of said first row relays for completing the first circuit to activate said first means, and means responsive to the activation of the relay associated with the third detector of the second row of detectors and to the partial completion of said first circuit and to the deactivation of the relay associated with the third detector of the first row of detectors for completing said second circuit to actuate said counter to indicate an additional vehicle change.

16. A system for counting vehicles passing along an access roadway of a parking garage or the like comprising two vehicle detectors spaced along the roadway for activation in a forward sequence by a vehicle passing along the roadway to enter the garage and in a reverse sequence by a vehicle passing along the roadway to leave the garage, a counter for indicating the cumulative algebraic total number of vehicles passing along the roadway, and means responsive to said detectors for actuating said counter to add one unit to the total in response to activation of said detectors in one of said sequences and to subtract one unit in response to activation of said detectors in the other one of said sequences, said detector responsive means being inoperative to actuate said counter in response to a successive actuation of. said detectors followed by deactivation of the second activated one thereof during the continued activation of the first 17. A system for counting vehicles passing along an access roadway of a parking garage or the like comprising two vehicle detectors spaced along the roadway for successive activation by a vehicle passing along the roadway in a selected direction, the spacing between said detectors being such that both detectors are activated for a common interval during the passage thereby in said selected direction of each vehicle to be counted yet such that they may be separately activated by respective successive vehicles, a counter, and means responsive to said detectors for actuating said counter including electrical circuit means for actuating said counter twice in response to the passage along the noadway of two successive vehicles spaced so closely that for :an interval one of the vehicles activates one of said detectors while the other vehicle activates the other detector.

18. A system for counting vehicles passing along an access roadway of a parking garage or the like comprising two vehicle detectors spaced along the roadway for activation in a predetermined sequence by a vehicle passing along the roadway in a selected direction, the spacing between said detectors being such that both said detectors are activated for a common interval during the p assage thereby of each vehicle to be counted yet such that said detectors may be separately activated by respective successive vehicles, a counter, means responsive to activation of said detectors in said predetermined sequence followed by the deactivation of the first activated one of said detectors for actuating said counter, and means operatively connecting said detector responsive means to said counter to render said counter operative to make a succeeding count even though said first activated detector is reactivated by a succeeding vehicle during the time the first vehicle continues to activate said second actuated detector. A

19. A system for counting vehicles passing along an entrance roadway of a parking garage or the like comprising first and second vehicle detectors spaced along the roadway for successive activation by a vehicle passing along the roadway in a selected direction, the spacing between said detectors being such that both detectors are activated for a common interval during the passage thereby of each vehicle to be counted yet such that they may be separately activated by respective successive vehicles, a counter, and means responsive to actuation of said detectors by vehicles moving in said selected direction tor actuating said counter twice upon (a) activation of said first detector by a first vehicle, (b) activation of said second detector by said first vehicle as it moves on in said selected direction, deactivation of said first detector as said first vehicle passes beyond said first detector, (d) reactivation of said first detector by a second vehicle moving in said selected direction, (e) deactivation of said second detector by said first vehicle passing beyond said second detector, (f) reactivation of said second detector by said second vehicle moving on in selected direction and (g) deactivation of said first detector by said second vehicle passing beyond said second detector.

20. A system for counting vehicles passing over an access roadway of a parking garage or the like, the roadway being sufiiciently wide to accommodate at least two vehicles abreast, said system comprising a plurality of vehicle detectors arranged in two longitudinally spaced, laterally extending rows adjacent to the roadway for detecting vehicles passing therealong, the lateral spacing between said detectors being less than the width of a vehicle to be counted, the number of detectors in each row being greater than the number of vehicles the roadway will accommodate abreast, the longitudinal spacing between said rows being such that at least one of said detectors of each row is activated for a common interval during the passage thereby of each vehicle to be counted yet such that corresponding detectors of the difierent rows maybe activated for a common interval by ditferent vehicles, a counter, and means responsive to said detectors for actuating said counter, said detector responsive means being operative to actuate said counter to indicate only a single count in response to a predetermined sequence of activation and deactivation of said detectors when only two adjacent detectors of each row are sequentially activated and deactivated, and being operative to actuate said counter to indicate a double count when two non-adjacent detectors of each row are activated and deactivated in said predetermined sequence.

21. A system for counting vehicles passing over an access roadway of a parking garage or the like, the roadway being sufiiciently wide to accommodate at least two vehicles abreast, said system comprising a plurality of vehicle detectors arranged in two longitudinally spaced, laterally extending rows adjacent to the roadway for detecting vehicles passing therealong, the lateral spacing between said detectors being less than the width of a vehicle to be counted, the number of detectors in each row being greater than the number of vehicles the roadway will accommodate abreast, the longitudinal spacing between said rows being such that at least one of said detectors of each row is activated for a common interval during the passage thereby of each vehicle to be counted yet such that corresponding detectors of the different rows may he activated for a common interval by different vehicles, a counter, and means responsive to said detectors for actuating said counter, said detector responsive means being operative to actuate said counter to indicate only a single count in response to a predetermined sequence of activation and deactivation of said detectors when only two adjacent detectors of each row are sequentially activated and deactivated, and being operative to actuate said counter to indicate a double count when two non-adjacent detectors of each row are activated and deactivated in said predetermined sequence, said detector responsive means being further operative while one of said detectors remains continuously activated and also while one of said detectors in one row and a corresponding detector in the other row remain continuously activated to actuate said counter in response to activation and deactivation in said predetermined sequence of one of said detectors nonadjacent to said one detector and of one of said detectors non-adjacent to said corresponding detector, whereby said system continues to count vehicles passing along a clear lane of the roadway while another vehicle remains parked blocking a lane.

References ited in the file of this patent UNITED STATES PATENTS 1,836,655 Dunford Dec. 15, 1931 2,603,419 Barker et a1. July 15, 1952 2,644,150 Burn June 30, 1953 2,784,911 Cooper Mar. 12, 1957 

21. A SYSTEM FOR COUNTING VEHICLES PASSING OVER AN ACCESS ROADWAY OF A PARKING GARAGE OR THE LIKE, THE ROADWAY BEING SUFFICIENTLY WIDE TO ACCOMODATE AT LEAST TWO VEHICLES ABREAST, SAID SYSTEM COMPRISING A PLURALITY OF VEHICLE DETECTORS ARRANGED IN TWO LONGITUDINALLY SPACED, LATERALLY EXTENDING ROWS ADJACENT TO THE ROADWAY FOR DETECTING VEHICLES PASSING THEREALONG, THE LATERAL SPACING BETWEEN SAID DETECTORS BEING LESS THAN THE WIDTH OF A VEHICLE TO BE COUNTED, THE NUMBER OF DETECTORS IN EACH ROW BEING GREATER THAN THE NUMBER OF VEHICLES THE ROADWAY WILL ACCOMMODATE ABREAST, THE LONGITUDINAL SPACING BETWEEN SAID ROWS BEING SUCH THAT AT LEAST ONE OF SAID DETECTORS OF EACH ROW IS ACTIVATED FOR A COMMON INTERVAL DURING THE PASSAGE THEREBY OF EACH VEHICLE TO BE COUNTED YET SUCH THAT CORRESPONDING DETECTORS OF THE DIFFERENT ROWS MAY BE ACTIVATED FOR A COMMON INTERVAL BY DIFFERENT VEHICLES, A COUNTER, AND MEANS RESPONSIVE TO SAID DETECTORS FOR ACTUATING SAID COUNTER, SAID DETECTOR RESPONSIVE MEANS BEING OPERATIVE TO ACTUATE SAID COUNTER TO INDICATE ONLY A SINGLE COUNT IN RESPONSE TO A PREDETERMINED SEQUENCE OF ACTIVATION AND DEACTIVATION OF SAID DETECTORS WHEN ONLY TWO ADJACENT DETECTORS OF EACH ROW ARE SEQUENTIALLY ACTIVATED AND DEACTIVATED, AND BEING OPERATIVE TO ACTUATE SAID COUNTER TO INDICATE A DOUBLE COUNT WHEN TWO NON-ADJACENT DETECTORS OF EACH ROW ARE ACTIVATED AND DEACTIVATED IN SAID PREDETERMINED SEQUENCE, SAID DETECTOR RESPONSIVE MEANS BEING FURTHER OPERATIVE WHILE ONE OF SAID DETECTORS REMAINS CONTINUOUSLY ACTIVATED AND ALSO WHILE ONE OF SAID DETECTORS IN ONE ROW AND A CORRESPONDING DETECTOR IN THE OTHER ROW REMAIN CONTINUOUSLY ACTIVATED TO ACTUATE SAID COUNTER IN RESPONSE TO ACTIVATION AND DEACTIVATION IN SAID PREDETERMINED SEQUENCE OF ONE OF SAID DETECTORS NONADJACENT TO SAID ONE DETECTOR AND OF ONE OF SAID DETECTORS NON-ADJACENT TO SAID CORRESPONDING DETECTOR, WHEREBY SAID SYSTEM CONTINUES TO COUNT VEHICLES PASSING ALONG A CLEAR LANE OF THE ROADWAY WHILE ANOTHER VEHICLE REMAINS PARKED BLOCKING A LANE. 